Relation of FEV₁to Clinical Outcomes during Exacerbations of Chronic Obstructive Pulmonary Disease

Abstract

FEV(1) is an objective measure of airflow obstruction used in clinical practice and in therapeutic trials. The precise relationship of FEV(1) to clinical outcomes is generally uncertain. As part of a randomized trial to assess systemic corticosteroid efficacy, we obtained serial FEV(1) measurements in patients hospitalized for exacerbations of chronic obstructive pulmonary disease (COPD). Over the first 14 Study Days at least one FEV(1) value was obtained in 261 subjects. Sixty-four of these subjects experienced treatment failure, defined as death, intubation, readmission for COPD, or intensification of drug therapy, by Study Day 30. After adjustment, both FEV(1) at entry into the study (odds ratio [OR] for a 100-ml increase, 0.87; 95% confidence interval [CI], 0.79 to 0.96) and change in FEV(1) over the first two Study Days (OR for a 100 ml increase, 0.80; 95% CI, 0.69 to 0.92) predicted treatment failure. We identified no baseline characteristic that was significantly related to FEV(1) at entry into the study. Assignment to the systemic corticosteroid treatment arm was associated with a significantly larger FEV(1) at Study Day two (p = 0.01). We conclude that FEV(1) measurements at admission and over the first several days of hospitalization are highly predictive of clinical outcomes during exacerbations of COPD.

The Adjunctive Effect of Nebulized Furosemide in COPD Exacerbation: A Randomized Controlled Clinical Trial

“…Niewoehner et al found that relatively small differences in FEV 1 have a substantial impact on clinical outcome. 20 Among the subjects who received nebulized furosemide, those with lower baseline FEV 1 had better dyspnea improvement (see the Figure). Since patients with lower FEV 1 are less able to bronchodilate, this improvement might also be attributed to an effect of nebulized furosemide on dyspnea relief that is independent of bronchodilation.…”

What is the optimal treatment strategy for chronic obstructive pulmonary disease exacerbations?

“…FEV1 measurements are a highly predictive factor in the clinical outcome of COPD exacerbations [20]. In contrast to other trials patients who had already received systemic steroids prior to hospital admission were not excluded.…”

Outcomes for COPD pharmacological trials: from lung function to biomarkers

“…In a study by NIEWOEHNER et al [37] of acute exacerbations of COPD, FEV1 change was associated with clinical response to treatment. An FEV1 improvement of ,100 mL was associated with a higher relapse rate.…”

“…However, even small changes in postbronchodilator FEV1 following acute treatment were found to be associated with meaningful clinical outcomes [36][37][38].…”

“…In another study more typical of clinical trials in COPD [470], 71 subjects in a crossover trial comparing tiotropium and formoterol had a mean FEV1 of 1.94 L (37% pred) with an SD of 290 mL. In a study of the effects of tiotropium on exacerbations, pre-treatment FEV1 was 1.60 L with an SD of 400 mL (35.6% pred) [37]. Applying the half SD MID estimate to these clinical therapeutic trials of patients with symptomatic COPD indicates a statistical MID estimate of 145-200 mL.…”